Terminal apparatuses typified by mobile phones, smartphones, and so on are generally equipped with location-determining functions, such as those of global positioning systems (GPSs). Thus, the user of each terminal apparatus can determine its current location. Also, by transmitting information about the current location to a server through a network, the user can receive various types of service information corresponding to the location. For example, in recent years, service providers have been offering travel guide services that deliver information about sightseeing spots in the vicinity of the current positions of users (for example, travelers) of terminal apparatuses, based on location information of the users. Related art is disclosed in, for example, Japanese Laid-open Patent Publication No. 2011-34402, Japanese Laid-open Patent Publication No. 2012-8659, Japanese Laid-open Patent Publication No. 2010-211679, and A. Monreale et al., “WhereNext: a Location Predictor on Trajectory Pattern Mining” Proc. KDD '09, pp. 637-645 (2009).